Download Hemodynamic Assessment

Hemodynamic Assessment:
Everything we do in the lab [30]
SCAI Fellow Course – Fall 2014
Ralf J Holzer MD MSc FSCAI
Medical Director
Cardiac Catheterization & Interventional Therapy
Interim Division Chief
Sidra Cardiovascular Center of Excellence
Purpose of
Diagnostic Cardiac Catheterization
Measure intracardiac pressures
Assess intracardiac blood flow / shunts
Assess pulmonary and systemic circulatory systems
Determine cardiac anatomy
Assess ventricular function
Assess valvular function
Measured Variables
Arterial blood pressure
Heart rate
Intra-cardiac pressures
Oxygen saturations
Blood gas
Calculated Variables
Cardiac index / output
Systemic vascular resistance
Pulmonary vascular resistance
Valve area
Aortic Pressure
Peak measurement
Dichrotic notch
LV Pressure
R wave
Isovolumetric contraction
End diastolic
Peak
measurement
Right Atrial Pressure
Pulmonary capillary wedge pressure
Recognize
Normality!!
Normal
Pressures
and
Saturations
Think while you
collect !!
Case Example
3 year old male
Born with critical PS, RV
hypoplasia, PFO, PDA
Neonatal period: BPV + Repeat
BPV with PDA stent (5*20mm)
Cath at age 18mo: Did not
tolerate PDA (test) occlusion
Hemodynamic Manipulation
Hemodynamics Immediately before
test Occlusion
Test Occlusion
After test Occlusion
Hemodynamic Changes
With test occlusion
Without test occlusion
… hemodynamic changes …
Slight increase in HR by ~ 10bpm with test occlusion
Increase in mean RA pressure by 3 and a-wave by ~5
Mild increase of TV gradient
No increase in RV pressure
BP grossly unchanged
Possibly small decrease in COP 3.3 -> 3
Patient suitable to go ahead with ASD/PDA
closure
Errors and Artifacts
Low-frequency responses: Air in line or failure in
flush device with formation of partial clot in catheter 
Over-damping.
Catheter whip: Motion of catheter tip itself produces a
noticeable pressure swing; not common in A-line but
common in PA catheter.
Change in electronic balance: electronic zeroing
should be done periodically to preclude baseline drift
(for example: due to change in room temperature).
Transducer position error
Resonance in peripheral vessels: The systolic
pressure measured in a radial artery may be up to
20~50 mmHg higher than in the central aorta.
Air Bubbles in the Line
Most common error and most common reason for
inaccurate pressure recordings
Air bubbles can result in a lower frequency response
and greater resonance response.
Small amount may augment systolic pressure reading;
while large amount cause an over-damped system.
Intracardiac Shunts
Evaluation of shunts requires:
Detection, classification, localization and quantitation
Step-up in oxygen saturations in normal patients:
<5%: Atrial 6%, Ventricular 4%, Great Vessel 4%
<1%: Atrial 9%, Ventricular 6%, Great Vessel 6%
Ratio of pulmonary to systemic flow:
Qp / Qs = (Ao Sat – SVC Sat) / (PV Sat – PA Sat)
What is the Shunt ? (Qp/Qs)
Case Example
20 months female
Recently to US from Thailand
Dx: Unbalanced R-dominant
CAVSD
H/o attempted Glenn which
was poorly tolerated
 Glenn converted to central
shunt
?
The pulmonary veins
????
Cardiac Output Calculations
Fick Principle
Fick Principle
Cardiac Output by
Oxygen Consumption
!!! STEADY STATE !!!
Oxygen Delivery
DO2 = [(1.34 x Hgb x SaO2) + (0.0031 x PaO2)] x CO x 10
Changes in Hgb, SaO2 and CO result in relatively large proportional
changes in oxygen content.
Changes in PaO2 result in relatively small changes in oxygen
content.
Systemic Cardiac Output
VO2 [ml/min*m2]
CO [l/min*m2] = -----------------------AVO2-Diff [ml/l]
CO
= Cardiac Output (indexed)
VO2
= Oxygen consumption (indexed)
AVO2-Diff
= Arteriovenous oxygen difference
(Ao Sat – SVC Sat) * (Hb) * (1.34) * (10)
Pulmonary Flow
VO2 [ml/min*m2]
CO [l/min*m2] = -----------------------AVO2-Diff [ml/l]
CO
= Cardiac Output (indexed)
VO2
= Oxygen consumption (indexed)
AVO2-Diff
= Arteriovenous oxygen difference
(PV Sat – PA Sat) * (Hb) * (1.34) * (10)
Oxygen Consumption
n Measured via
n
n
Douglas bag
Polarographic method, Metabolic Hood
n Estimate in adults: 3ml O2/kg or 120 ml/min*m2
Beware its limitations!!
n Pediatric estimate: 150 ml/min*m2
n Estimated via Method by Lafarge and Meittinen
n
n
Male 138.1 – 11.49 ln (age) + 0.378 (heart rate)
Female 138.1 – 17.04 ln (age) + 0.378 (heart rate)
n Lundell et al (Pediatric Cardiology 1996) [< 3 years]
n
3.42 * height (cm) − 7.83 * weight (kg) + 0.38 * HR − 54.
Cardiac Output – Thermodilution
Double lumen thermodilution catheter
Proximal port for injection of saline (usually RA)
Thermistor distally near catheter tip (usually PA)
Usually automated system with calculations via
computer
Cardiac Output – Thermodilution
Thermodilution
Guidelines for Injection
Injection port: CVP
Solution: Normal Saline
Injection Temperature: ice or room temperature
Volume: 5 or 10cc (usually 5cc)
Injection time: Usually within 4seconds
Consecutive 3 measurements are required.
Serial measurement: differ less than 10-15%
Thermodilution: Sources of Errors
Unreliable in presence of significant TR
Volume to low: Falsely high CO
Volume to high: Falsely low CO
Injection time too long: Falsely low CO
Thermodilution tends to overestimate CO in patients with
low CO
Be careful in presence of shunts!
Vascular Resistance
Ohm’s Law:
R=U/I
Vascular resistance =
Change in pressure / Flow
Vascular Resistance
(Mean PA – Mean LA) [mmHg]
RPi = ------------------------------------------------ ~ <3 Um2
(Pulmonary blood flow) [l/min m2]
(Mean Ao – Mean RA) [mmHg]
RSi = ------------------------------------------------- ~ <20 Um2
(Systemic blood flow) [l/min m2]
PVRi ?
1 year, Hb 11g/dl
PVRi ?
Adult, Hb 12g/dl
PVRi ?
2 weeks, Hb 12g/dl
Calculation of Valve Area
Gorlin et AL, Am Heart J, 1951
Systolic/Diastolic flow
Valve area = -----------------------------------C * 44.5 * SQRT(Mean Gradient)
CO * (RR Interval)
Syst./Diast. Flow = --------------------------60*Syst/Diast .Eject.Time
Valve Area [cm2], Syst.Flow [ml/sec],
CO [ml/min], RR[sec], Syst.Ej.Time [sec]
Aortic
Mitral
2.0 - 3.0 cm2
4.0 - 6.0 cm2
Utilize all the tools you have at
your disposal to obtain the
information you need !!
Case Example:
HLHS, s/p Hybrid Stage I Palliation
Damped waveform across pulmonary artery band caused by 4 Fr. Judkins
right coronary catheter
0.014” Pressure Wire
RADI® wire
Volcano
Primewire®
Case Example:
HLHS, s/p Hybrid Stage I Palliation
Case Example:
HLHS, s/p Hybrid Stage I Palliation
Damped waveform across pulmonary artery band caused by 4 Fr. Judkins
right coronary catheter
Undamped waveform utilizing pressure wire across pulmonary artery band
Case Example
39 year old female
S/P Mustard for dTGA at 6 months
Epicardial VVIR PPM (AVN dysyfunction, SNDz)
Palpitations and (pre) syncope
Echo: Qual. Mild-moderately reduced RV function,
moderate RAVV regurgitation, mild sub-PS, possible
superior baffle limb stenosis
Baseline Hemodynamics
Baseline Hemodynamics
Baseline Hemodynamics
Direct Evaluation of
Pulmonary Venous Baffle
Baseline Hemodynamics
Pressure wire for sub-PS
MPA
Sub pulmonary valve
LV
Stenting of Atrial Baffles
Get accurate data and don’t just
blindly trust what you see on the
screen!
Simultaneous pressure recordings
Flow across normal MV
Case Example
16 year old female
h/o repair of supravalve mitral
membrane and resection of
sub-AS
Exercise intolerance and SOB
Echo: Residual mitral stenosis
(3-4mmHg mean gradient)
and mild MI, Mild residual sub
-AS (20mmHg), mildly
impaired LV
 Considered for MV surgery
PCW / LVEDP
-
Direct LA / LVEDP
Subaortic Stenosis
Hemodynamics prior to ASD closure
Case Example
56 year old female
Exertional dyspnea and chest pain
H/o hypertension, type II diabetes, hyperlipidemia
Echo: Moderate secundum ASD
Cath (adult hospital): Mean PA presure 28, Qp:Qs 2.9:1,
isolated plaque coronary dz
Cardiac Meds: Valsartan
Baseline Hemodynamics
Qp:Qs ~ 4.1:1
ASD ‘Test’ Occlusion
ASD ‘Test’ Occlusion
Case Example
22month, h/o CAVSD repair)
Cardiac Tamponade
DD - Constriction-Restriction
Square Root Sign
Conclusions
Hemodynamic Catheterization is an ‘Art’ and often
more complex than many interventional procedures
Meticulous attention to detail is required
Have a game plan and know what the cath should
answer and reassess whether these questions have
been answered before finishing a procedure
Evaluate and re-evaluate everything that does not
make sense or is unexpected until you can prvide a
logical explanation
Review all your data before completing a case
A cath that is performed without answering the
question it had intended or a cath that need to be
repeated due to this, should be considered an
adverse event!